The gut (gastrointestinal tract) processes food – from the time it is first eaten until it is either absorbed by the body or passed out as stools (feces). The process of digestion begins in the mouth. Here your teeth and chemicals made by the body (enzymes) begin to break down food. Muscular contractions help to move food into the gullet (esophagus) and on to the stomach. Chemicals produced by cells in the stomach begin the major work of digestion.

While some foods and liquids are absorbed through the lining of the stomach, the majority are absorbed in the small intestine. Muscles in the wall of the gut mix your food with the enzymes produced by the body. They also move food along towards the end of the gut. Food that can’t be digested, waste substances, germs (bacteria) and undigested food are all passed out as feces.